1. Field of the Invention
The present invention relates to image processing in photogrammetry.
2. Description of the Related Art
Photogrammetry is being widely used in making maps and is also being used as an extremely effective tool in recording local conditions at examinations of the scenes of traffic accidents for example. Conventionally, in photogrammetry, a stereo camera system consisting of two cameras, fixed at a distance away from each other, is used so as to calculate the three-dimensional coordinates of surveyed points from the two images captured by the two cameras. The stereo camera system is a large, heavy piece of equipment. Further, the calculation of the three-dimensional coordinates requires recording of detailed information such as the positional information and angle of inclination of the camera and the measured length of a target object etc. The surveying work is both complicated and hard in terms of labor. Further, a sufficiently clear photographic environment often can not be secured, such as when there are obstacles in the area surrounding the scene of a traffic accident. Often examination of the scene by stereo camera systems is difficult.
Therefore, the assignee has proposed a large number of photogrammetric methods using single lens cameras (Japanese Unexamined Patent Publication (Kokai) No. 10-293026 and Japanese Unexamined Patent Publication (Kokai) No. 10-221072) and targets to be included in pairs of images (hereinafter referred to as xe2x80x9cpaired imagesxe2x80x9d) for improving the precision of photogrammetry (Japanese Unexamined Patent Publication (Kokai) No. 10-307025, Japanese Unexamined Patent Publication (Kokai) No. 10-293026, Japanese Unexamined Patent Publication (Kokai) No. 10-185563, Japanese Unexamined Patent Publication (Kokai) No. 10-185562, Japanese Unexamined Patent Publication (Kokai) No. 10-170263, and Japanese Unexamined Patent Publication (Kokai) No. 10-141951) for realizing efficient photogrammetry with simple equipment.
Such a photogrammetric method obtains paired images taken of the same target and survey object from different directions and uses a mouse or other input means in a specialized photogrammetric image processing apparatus to manually designate surveyed points commonly included in the paired images (hereinafter referred to as xe2x80x9cphysical pointsxe2x80x9d) and thereby survey any range based on these points.
Since a large number of paired images are used when the survey extends over a broad range, the manual finding and designating of the corresponding physical points in each of the paired images becomes complex, of course. Further, considering the need for survey precision, selection of the physical points to obtain sufficient precision is extremely complicated even for a skilled operator.
The survey maps obtained from the large number of paired images are connected together. At the time of making the map, it is difficult to identify which positions of the surveyed range the obtained survey maps show and therefore it is necessary to designate a large number of physical points. Therefore, the work efficiency drops significantly.
An object of the present invention is to provide a photogrammetric image processing apparatus, a photogrammetric image processing method and a storage medium, in which a photogrammetric image processing program is stored, by which a large improvement in efficiency of the manual work in photogrammetric image processing is achieved.
According to a first aspect of the present invention, there is provided a photogrammetric image processing apparatus defining a plurality of images commonly including a target at a predetermined position as being in the same group, calculating the camera position of the photographing camera taking each image and the inclination of its optical axis for each image, designating a common physical point in each image, calculating three-dimensional coordinates of the physical point, and generating a survey map based on the three-dimensional coordinates, comprising a display processor that has a image display area for displaying all of the images belonging to the same group, and a drawing area for displaying that survey map, an area computing processor that calculates a valid mapping range of the same group, which is shown in that drawing area, based on the camera position and the optical axis inclination, and a control processor that displays images of a predetermined group in that image display area, and displays that valid mapping range of that predetermined group in that drawing area.
According to a second aspect of the present invention, there is provided a photogrammetric image processing method defining a plurality of images commonly including a target of a predetermined shape provided at a predetermined position and enabling output of an amount of displacement and rotational angle from an initial state as belonging to the same group, calculating the camera position of the photographing camera taking each image and the inclination of its optical axis for each image, displaying that image in an image display area of a display processor and designating a common physical point in that image contained in that image display area, calculating three-dimensional coordinates of that physical point, generating a survey map based on the three-dimensional coordinates, and displaying that survey map in a drawing area of that display processor, comprising a first step of calculating a range of guaranteed precision corresponding to each image based on the camera position and the optical axis inclination of each image included in the same group, a second step of calculating an overlapping area of the ranges of guaranteed precision of that image of the same group to obtain a valid mapping range of the same group, and a third step of displaying images of a predetermined group in that image display area, and displaying that valid mapping range of that predetermined group in that drawing area.
According to a third aspect of the present invention, there is provided a storage medium storing a photogrammetric image processing program defining a plurality of images commonly including a target of a predetermined shape provided at a predetermined position and enabling output of an amount of displacement and rotational angle from an initial state as belonging to the same group, calculating the camera position of the photographing camera taking each image and the inclination of its optical axis for each image, displaying that image in an image display area of a display processor and designating a common physical point in that image contained in that image display area, calculating three-dimensional coordinates of that physical point, generating a survey map based on the three-dimensional coordinates, and displaying that survey map in a drawing area of that display processor, that photogrammetric image processing program including a routine for calculating a range of guaranteed precision corresponding to each image based on the camera position and the optical axis inclination of each image included in the same group, a routine for calculating an overlapping area of the ranges of guaranteed precision of that image of the same group to obtain a valid mapping range of the same group, and a routine for displaying images of a predetermined group in that image display area, and displaying that valid mapping range of that predetermined group in that drawing area.